According to current law, you would need to use it as your Main Home for at least 2 years to avoid PART of the gains. That would be prorated, and there would be no way to avoid all of the gain.
Proposed law in Congress may change that rule to using it as your Main Home for 5 years.
If you 'just sold' it and purchase another property in a separate transaction, the sale of the rental would still be taxable. However, if you do a qualified "1031 Exchange", that can defer that gain into the new rental property. You would need to use a 3rd party administrator that specializes with 1031 Exchanges to do that.
